(ISB) of Oil - U.S. National Response Team (NRT)

2. That the burn will be

2. That the burn will be monitored for the safety of cleanup crews and potentially affected populations and will be stopped if safety standards can not be maintained. That sea and weather conditions must allow for an effective burn 3. Optimal environmental conditions: C winds less than 20 knot (23 mph or 37 km/hr) C waves less than 2-3 feet (62 to 92 cm) C currents less than 3/4 knot (0.9 mph or 1.4 km/hr) relative velocity between the boom and the water 4. Required oil conditions: C minimum thickness: < 0.08 to 0.12 inches (2 to 3 mm) for fresh crude oil < 0.12 to 0.2 inches (3 to 5 mm) for diesel and weathered crude < 0.2 to 0.4 inches (5 to 10 mm) for emulsions and Bunker C C less than 30% evaporative loss (for most crude oils) C water content less than 25% (for oil-in-water emulsions with water contents greater than 25% an emulsion breaker may be needed to obtain ignition) Q. Why would you want to conduct ISB? Oil is harmful to the environment. ISB is an effective technique for removing oil from the water surface. An oil spill can have adverse effects on a variety of natural resources: fisheries, terrestrial and marine mammals, shellfish beds, recreational beaches, and birds. This, in turn, can have significant impacts on the people who rely on these natural resources for their economic, cultural, and recreational well-being. ISBoffers a practical method for removing large quantities of oil very quickly, thereby minimizing the environmental exposure to oils’ long-term effects. Q. Shouldn’t we be more worried about preventing the spill instead of burning? Preventing spills is our number one priority. The oil industry and certain state and federal agencies are working hard to prevent spills from happening. There are both federal and state laws and regulations that address prevention. Despite everyone’s efforts, however, spills happen, and the response community must be prepared to use all appropriate tools to respond effectively. Q. Is ISB the answer to all spill response? ISB is a useful spill response tool in certain circumstances. There are situations where burning may be the only means of eliminating large quantities of oil quickly and safely. There are also situations in which burning cannot be used. No two spills are the same. Burning should only be used where it can be done safely. Because of the decisions involved in using ISB, certain approvals must be obtained prior to its use. Agreements between state and federal regulatory authorities establish areas and necessary conditions where rapid decisions on ISB may be made by the Federal On-scene Coordinator and/or State On-scene Coordinator. Q. How quickly can ISB remove oil from the water? For thick layers of oil (greater than 0.5 inches) the oil removal rate is approximately 4.2 gallons of oil per hour for every square foot of oil on fire. For example, a fire covering 50 x 50 feet (2.500 square feet) would consume about 10,500 gallons of oil per hour under optimal conditions. Q. What are the emissions from an oil fire? The primary constituents of an oil fire are gases and particulates. The most abundant combustion products of crude oil are carbon dioxide and water vapor, which account for 70-85% of the combustion products. Particulates comprise 5- 15% and carbon monoxide, sulfur dioxide, oxides of nitrogen, aldehydes, ketones, and other combustion products are present in the sub % range. The particulate portion of the smoke is mostly carbon which produces the dark color of the

smoke. The emissions from the fire can also include hydrocarbons, including very low levels (less than 0.1 parts per million) of polyaromatic hydrocarbons. Q. How long will the smoke stay in the air? How long the smoke stays in the air depends on the weather conditions at the time of the spill. Some parts of the plume may stay in the general area of the burn for several hours after the burn is completed--and in unusual circumstances, days--but the thickest part of the plume will usually dissipate within a few hours. Q. What happens to the smoke when the fire occurs? Because of the intense heat, the smoke plume usually goes up into the atmosphere several hundreds to several thousands of feet, depending on the size of the burn and on the wind speed. It then levels off and is blown by the wind and moves according to the weather conditions at the time. Some parts of the plume may dip back down toward the surface but the majority of the smoke usually stays well up in the air. Q. Is it dangerous? When well planned, burning spilled oil is a very safe clean-up method. The burning will be planned, controlled, and monitored and will occur over a short period of time. The byproducts of burning oil are similar to the burning or combustion of other products such as gasoline in cars, firewood, home and industrial heating and power generation. However, an in situ burn is less efficient than the burning or combustion of gasoline in cars, which is why the fire produces a lot of smoke. An oil fire produces black particles of carbon, water vapor and invisible gases. These byproducts from the oil burn will not pose a threat to populated areas. If there is a concern that the general public may be exposed to smoke from the burning oil, we will monitor particulate concentrations in populated areas. Q. What will be released into the environment when you burn the oil? Burning the oil will produce a dense cloud of black smoke. Depending on wind direction and weather conditions, you might be able to see the smoke from the shore. The smoke is black because of the black particles of carbon. The most abundant combustion products of crude oil are carbon dioxide and water vapor, which account for 70-85% of the combustion products. Particulates comprise 5-15% and carbon monoxide, sulfur dioxide, oxides of nitrogen, aldehydes, ketones, and other combustion products are present in the sub % range. Scientists have studied gases from oil fires. These studies have shown that the concentration of gases produced during in situ burning, are within safe levels for humans beyond three miles downwind of the source. The burn is planned so that the smoke should not travel over any populated areas. The gas concentrations will not be around long enough nor at levels high enough to cause public harm. Q. How long will the burn last and how rapidly will the oil burn? The oil burning and the smoke it produces will be visible for only a few hours. The smoke will dissipate within these few hours. Burning removes oil from the water surface at a rate of 4 gallons of oil per hour, for every square foot of oil on fire. For example, a fire covering about 2,500 square feet (50 by 50 feet of oil), would consume about 10,500 gallons of oil per hour, under optimal conditions. Q. What clean-up methods are possible? There are three clean-up methods: in situ burning, dispersants and mechanical methods. In situ burning burns the spilled oil on the water, safely removing nearly all of the contained oil from the water. Dispersants are specially designed products that break the oil slick into small particles, which then disperse into the water column. Mechanical response uses physical barriers and mechanical devices, such as containment booms and skimmers, to redirect and remove oil from the surface of the water. There is also the option of doing nothing, allowing natural recovery. Responders will determine what clean-up methods to use based on the potential shoreline and natural resource impacts, the size, location, and type of oil spilled, weather, and other variables. In a major oil spill it may be possible for all